Phase change material insulation for containers

ABSTRACT

Phase change materials (PCM) such as a liquid salt hydrate may be stored in capsules of various sizes and applied to fabrics and fibers to fabricate PCM features that provide passive temperature control for shipping containers and goods. In one implementation, PCM fabric covers may be placed over palletized cargo and over individual goods. Modular fabric pieces may be combined and interconnected to cover goods. Fabric covers may emphasize thermal performance over comfort or aesthetics when selecting microcapsule size and coating materials. In another implementation, PCM capsules may be combined with fiber filler, shaped as desired, and sealed within an exterior skin to produce rigid PCM panels having various shapes. Panels may be used to line interiors or exteriors of shipping containers or goods. Panels may be shaped to include contours that fit snugly against a desired surface, or to include interior portions in which goods can be fit into.

PRIORITY

This application claims priority to U.S. Provisional Application No. 62/958,361, entitled “Phase Change Material Insulation For Containers,” filed on Jan. 8, 2020, the disclosure of which is incorporated by reference herein.

FIELD

The disclosed technology pertains to phase change material insulators for providing passive cooling of shipping containers and storage containers.

BACKGROUND

Advancements in shipping containers and storage containers have been driven by the increasing quantity, cost, fragility, and perishability of goods that may be shipped using standard infrastructure (e.g., ground and air vehicles used to ship mail and other packages containing non-perishable goods). With such advancements, expensive medicines, electronics, and other goods that may previously have been delivered by a specialized courier services may instead be packed in specialized shipping containers and transported along standard transit routes.

Goods shipped in such containers may have thresholds for such factors as temperature, motion, humidity, and other characteristics during storage and transport. Deviations outside of acceptable ranges for these characteristics may affect the quality or efficacy of a shipped good, or in some cases may even completely ruin a good or make it harmful when used for its intended purpose.

Sensitive goods may be shipped in containers that include active protection features, passive protection features, or both. Active protection features may include temperature control, climate control, internal power supplies, location tracking, and other features. Passive protection features may include insulation materials, shock absorption materials, electromagnetic shielding, and other features.

While active protection features often provide the highest level of protection for sensitive goods, they are often the most complex and most expensive to implement and support. As a result, passive protection features may be combined with active protection features in order to improve overall performance of the shipping container, or may be used as a sole means of protection where appropriate (e.g., goods having low or moderate sensitivity, goods being shipped for short distances). Passive protection features for maintaining temperature or other climate aspects within a shipping container are typically limited in both the extent and the duration for which they can influence temperature. As an example, a block of ice may be considered a passive temperature protection feature that cools the air within a container, as well as any other surfaces or materials that the ice is in direct contact with.

However, the temperature control provided by a block of ice will be limited both by the ice's own temperature (e.g., the temperature to which the ice is cooled prior to being placed in the shipping container) as well as the period of time that it takes to completely melt. Insulation materials and other conventional passive temperature protection features are limited in other ways. As a result, passive temperature protection features are typically incorporated into shipping containers due to their low cost and simplicity rather than their overall effectiveness relative to active temperature protection features.

What is needed, therefore, is an improved passive temperature protection feature for shipping containers.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings and detailed description that follow are intended to be merely illustrative and are not intended to limit the scope of the invention as contemplated by the inventors.

FIG. 1 shows a perspective view of an exemplary shipping container;

FIG. 2 shows a front elevation view of the shipping container of FIG. 1 with a set of doors opened;

FIG. 3 shows a perspective view of another exemplary shipping container;

FIG. 4 shows a front elevation view of the shipping container of FIG. 2 with a set of doors opened.

FIG. 5 shows a perspective view of a cargo pallet including an exemplary cover;

FIG. 6 shows a cross sectional view of an exemplary material of the cover of FIG. 5;

FIG. 6A shows a cross sectional view of an exemplary polymer microcapsule of the material of FIG. 6;

FIG. 7 shows a schematic diagram showing components of an assembled cargo pallet;

FIG. 8 shows a perspective view of an exemplary modular cover;

FIG. 9 shows a perspective view of the modular cover of FIG. 8 focused on an exemplary conditioning indicator;

FIG. 10 shows a cross sectional view of modular cover of FIG. 8 including the conditioning indicator;

FIG. 11 shows a perspective view of an exemplary envelope;

FIG. 12 shows a perspective view of an exemplary panel;

FIG. 13 shows a cross sectional view of the panel of FIG. 12;

FIG. 14 shows a perspective view of the shipping container of FIG. 3 with a plurality of panels installed;

FIG. 15 shows a perspective view of an exemplary door panel from the plurality of panels of FIG. 14;

FIG. 16 shows a perspective view of an exemplary molded panel usable with a medical device; and

FIG. 17 shows a flowchart of a set of exemplary steps that may be performed to prepare and use panels with shipped goods.

DETAILED DESCRIPTION

The inventors have conceived of novel technology that, for the purpose of illustration, is disclosed herein as applied in the context of temperature control for shipping containers. While the disclosed applications of the inventors' technology satisfy a long-felt but unmet need in the art of temperature control for shipping containers, it should be understood that the inventors' technology is not limited to being implemented in the precise manners set forth herein, but could be implemented in other manners without undue experimentation by those of ordinary skill in the art in light of this disclosure. Accordingly, the examples set forth herein should be understood as being illustrative only, and should not be treated as limiting.

Variations on the methods, features, and devices described herein may be implemented to provide advanced phase change material (PCM) based passive temperature control for shipping containers and other applications. Such PCM features are advantageous in providing additional or alternative passive temperature control, and thus may be used in conjunction with or as a replacement for conventional passive temperature control features such as ice, insulation, air gaps, and other features. While water (e.g., water in liquid form or, as ice, water in solid form) may itself be considered a basic PCM, the use of water is not always possible or appropriate for shipping containers. As an example, shipped goods are often sensitive to water, and so the use of water as a basic PCM introduces additional risks and requires additional safeguards and systems to address such risks. Additionally, when water is frozen into blocks it may melt unevenly during phase change back into a liquid. Thus, ice cannot maintain a consistent desired form throughout phase change, making it inappropriate for precise contact packing in and around surfaces of a container or good. Additional challenges with water as a basic PCM include weight, difficulty of transport in liquid and solid forms, risk of contamination over time, evaporation, and general fluid dynamics (e.g., movement of water within a container that may shift the containers center of gravity).

As an example of an advanced PCM, a liquid salt hydrate may be encapsulated into a polymer microcapsule of varying sizes that is able to contain the liquid through multiple phase change cycles. When the microcapsule is conditioned for freezing temperatures, the salt hydrate will freeze within the capsule. When exposed to a later temperature differential, the salt hydrate will phase change back to a liquid while absorbing thermal energy from its surroundings. While in liquid state, the impermeable microcapsule prevents the salt hydrate from evaporating or otherwise escaping.

Microcapsules or other advanced PCMs may then be incorporated into coatings or other treatments that may be applied to target objects. As described herein, advanced PCM coatings and treatments may be advantageously implemented to provide a variety of features and applications for shipping containers. By improving passive temperature control for shipping containers such implementations may reduce the burden on active temperature control features and, in some cases, allow for certain goods that typically require active temperature control to instead be shipped using only passive temperature control.

FIGS. 1 and 2 each show a shipping container (10) that may benefit from some or all of the PCM features described. The shipping container (10) includes a structure (12) (e.g., walls, ceiling, and floor, typically produced with one or layers of materials that are durable and/or provide a high insulation value) and a set of doors (14) that may be opened to provide access to an interior (16). The size and layout of the interior (16) may be varied for particular applications. As an example of a shipping container having a different overall size and shape, FIGS. 3 and 4 each show an alternate shipping container (30). Similar to the shipping container (10) of FIG. 1, the shipping container (30) includes a structure (32) (e.g., walls, ceiling, and a floor) and doors (34) that may be opened to provide access to an interior (36). By varying the size and shape of the interior (16, 36), shipping containers that are suitable for varying purposes may be provided.

For example, the shipping container (10) of FIG. 1 may have dimensions that are suitable for transport in larger aircrafts, while the shipping container (30) of FIG. 3 may have dimensions that are suitable for transport in smaller aircrafts or ground vehicles. Evolutions in shipping markets, shipping vehicles, shipping and practices continue to drive demand for a wide variation in size and shape of interior and exterior portions of shipping containers. As a result, it may be advantageous to provide PCM features that can be readily adapted for various uses.

I. PCM Fabric Covers

FIG. 5 shows a perspective view of a fully assembled cargo pallet (40) that includes a PCM cover (100). When assembled, a set of cargo (44) (e.g., one or more stacked or placed boxes, packages, or other objects) is arranged on a pallet (42). The cargo (44) may be secured to the pallet by straps, tape, wrap, or other means and is typically stacked and arranged to provide a roughly cuboid overall shape for the cargo pallet (40). Where a particular set of goods is irregularly shaped or otherwise unsuitable for arrangement as a cuboid, additional boxes, frames, or other sub-structures may be added to the cargo pallet (40) to provide additional protection and shaping, if desired. When assembly of the cargo pallet (40) is completed, the PCM cover (100) may be placed over the cargo (44) to provide additional insulation and passive temperature control. An edge (102) of the PCM cover (100) is shown as being partially pulled back to expose the cargo (44) within. When installed, the edge (102) overlaps with another edge (103) of the PCM cover (100) to minimize the possibility of exposure of the cargo (44). The edges (102, 103) may additionally be coupled to each other with buttons, ties, Velcro, adhesives, zippers, or other fastening means.

In some implementations, the edges (102, 103) of the PCM cover (100) may be in different positions to allow for varying ways in which it can be placed onto or provide access to the cargo (44) (e.g., a flap may hang from a top of the PCM cover (100) and may couple with overlapping edges on one or more sides). In some implementations, the PCM cover (100) may not include any openable flap portions, and instead may be slid onto the cargo (44) from above Other variations on the shape and characteristics of the PCM cover (100) exist and will be apparent to those of ordinary skill in the art in light of this disclosure.

Once in place, the PCM cover (100) provides a passive temperature control advantage for the cargo (44), especially where a snug fit between the PCM cover (100) and the cargo (44) can be achieved. With reference to FIG. 6, that figure shows a cross sectional view of a material of the PCM cover (100). The PCM cover (100) may be implemented with one or more layers, as may be desirable for a particular implementation. The layers shown in FIG. 6 include an outer layer (104), a core (106), and an inner layer (108). The core (106) will typically provide most or all of the PCM based temperature control, while the other layers may be selected to provide protection for the core (106), to provide additional insulation, or to aid in heat exchange between the core (106) and proximate cargo (44). As an example, the outer layer (104) and the inner layer (108) may each be a flexible thermal foil that reflects radiant heat. In this example, the core (106) may be a flexible cloth layer that has received a PCM treatment (e.g., the cloth may have been soaked in or coated with liquid polymer or adhesive that carries a plurality of polymer microcapsules).

Referring to FIG. 6A, an exemplary polymer microcapsule 120 is shown comprising a liquid salt hydrate 122 encapsulated in a polymer 124.

Microcapsule 120 may vary in size such that microcapsule 120 is able to contain the salt hydrate 122 through multiple phase change cycles. For instance, when microcapsule 120 is conditioned for freezing temperatures, the salt hydrate 122 can freeze within microcapsule 120. When exposed to a later temperature differential, the salt hydrate 122 can phase change back to a liquid while absorbing thermal energy from its surroundings. While in liquid state, polymer 124 inhibits the salt hydrate 122 from evaporating or otherwise escaping.

With such an arrangement, the cargo (44) receives the reflective benefit of two layers of thermal foil (104, 108), an insulation value from the cloth of the core (106), and also a phase change initiated heat absorption from the PCM treatment of the cloth (106). When the PCM cover (100) is conditioned prior to use (e.g., by placing into a freezer or other cooled environment to reduce the temperature of a PCM such as a salt hydrate) the resulting equivalent insulation value or passive temperature control value exceeds that of cloth or foil alone.

The thickness of each layer and the type of material used for each layer may be varied depending upon a particular application, and the number of layers may also be varied, with such variations being apparent to those of ordinary skill in the art in light of this disclosure. For example, some implementations may lack an inner layer (108) so that the core (106) may directly contact the cargo (44). Some implementations may include two core layers and three foil layers to further increase the volume of PCM microcapsules carried by the PCM cover (100). Layer type may also vary across the PCM cover (100). For example, flat sides of the PCM cover (100) may include a core layer (106) that is semi-rigid and provides a higher concentration or larger size of PCM microcapsules, while each corner (105) of the PCM cover (100) includes a core layer (106) that is more flexible due to a lower concentration or smaller size of PCM microcapsules.

The above described use of PCM treated fabric to implement the core (106) differs from conventional PCM fabric uses in a number of ways. Typically, PCM fabrics are incorporated into personal goods such as cold weather garments, athletic garments, sleeping bags, and other goods that a person is in direct contact with during use. In such scenarios, user comfort (e.g., breathability, comfort against skin, flexibility) is a primary concern. When implementing the core (106) the PCM treatment of fabric can instead maximize thermal performance (e.g., by increasing the size or concentration of microcapsules, or characteristics of the carrier fluid used in coating or treating) without regard to comfort. As a result, the PCM carrier fluid that is applied to the core (106) may dry or cure as a semi-flexible rubberized coating having its own insulation value and carrying a high concentration of encapsulated PCM.

Covers such as the PCM cover (100) may be readily implemented in different sizes and shapes to provide custom fitting to cargo or to provide a variety of standard sizes. Additionally, while the cargo pallet (40) includes one cover, multiple covers may be used when preparing a cargo pallet. As an example, FIG. 7 shows a schematic diagram showing interior components of an assembled cargo pallet such as the cargo pallet (40). Individual loads of cargo (e.g., separate goods, goods from separate customers) are represented as boxes, while PCM covers are represented as dashed lines. The PCM cover (100) can be seen surrounding the entire cargo pallet (40). A cargo load (45) is positioned on the pallet (42) and a second PCM cover (110) is placed on and surrounds the cargo load (45). Two additional cargo loads (46, 47) are positioned in a stack on the pallet (42), and each additional cargo load (46, 47) is also wrapped by an individual PCM cover (112, 114). In this manner, several layers of PCM covering may be provided, including a layer that surrounds all of the goods as well as individualized layers as may be desired for particular goods.

The flexibility in size and shape that PCM covers may be produced in allows for goods to be wrapped in a desired number of layers. For example, room temperature produce placed on a pallet may only require a single layer of PCM covering during transit while a batch of liquid medicine may require several layers, such that the cargo (46) includes additional internal PCM cover layers not shown in FIG. 7 (e.g., additional covers for internal boxes or packages, or PCM fabric sleeves in which one or more vials or bottles of a medicine may be placed during transit).

In addition to providing PCM covers as described, other PCM fabrics and structures may be implemented for use in shipping containers. As an example, FIG. 8 shows a perspective view of an exemplary modular cover (200). The modular cover (200) is shown as a rectangular section of PCM treated fabric, having characteristics and variations such as those described above in the context of the PCM cover (100). When preparing goods for shipment in a shipping container, multiple modular covers (200) may be connected to each other and used to cover, surround, or wrap goods (e.g., individual boxes and/or entire pallet loads, as shown in FIG. 7), or may be placed individually on top of, between, or within shipped goods. A surface (202) of the modular cover (200) includes two overlapping edges (204, 205) that include corresponding buttons, ties, zippers, Velcro, or other fasteners to allow for multiple modular covers (200) to be attached end to end to create a desired shape or size of PCM cover.

It should also be understood that a modular cover may have more than two connecting or overlapping edges as may be desired, or may couple together in positions other than along an edge. For example, in some implementations the modular cover (200) may have more than two overlapping and interconnectable edges. As another example, some implementations of the modular cover (200) may not have dedicated edges for coupling, and instead may have a plurality of Velcro sections across the surface (202) that may couple with a back surface opposite the surface (202). In this manner, the modular covers (200) may be coupled together in nearly any desired shape whether rectangular or irregular.

Some implementations of the modular cover (200) also include a conditioning indicator (206) that indicates the extent to which the modular cover has been conditioned (e.g., cooled and/or frozen) prior to use. FIG. 9 shows a magnified view of the conditioning indicator (206) extending from the surface (202), though it should be understood that it may also be fully or partially embedded within the body of the modular cover (200), or may rest entirely on top of the surface (202) (e.g., an adhesive temperature label or indicator). The conditioning indicator includes a visual indicator (208) that provides some visual indication of the conditioning (e.g., the temperature) of the core (106) of the modular cover (200). This may include a changing color, a changing pattern, a moving needle, or, where the conditioning indicator (206) includes a power supply, a digital numerical display of a detected temperature.

FIG. 10 shows a cross sectional view of the modular cover (200), with the conditioning indicator (206) implemented as a partially embedded temperature sensor. A probe (210) is embedded within the surface (202) and reaches the core layer (106). The probe (210) may provide electrical signals (e.g., current, a change in voltage, etc.) or may provide a thermally conductive path that is coupled to the body of the conditioning indicator (206). In the case of a digital thermal conditioning indicator, output would be displayed via the visual indicator (208) based on signals received from the probe (210). In other implementations, a thermochromic material within the conditioning indicator (206) would be cooled by the surface (202) and/or probe (210) and would change colors to indicate a current temperature, or change colors to indicate when a temperature threshold was reached. In this manner, multiple modular covers (200) may be stored in a conditioning area (e.g., a freezer) and, when needed, may be selected and used based upon feedback from conditioning indicators (206). As such, it may be advantageous for the conditioning indicator (206) to be placed near or on an edge of the surface (202), or on a cable that extends from the surface (202), in order to aid in later visual confirmation of conditioning from amongst many modular covers (202) that are stacked on shelves or arranged in rows.

Other variations in the design and placement of conditioning indicators (206) exist and will be apparent to those of ordinary skill in the art in light of this disclosure. It should also be understood that conditioning indicators may also indicate when modular covers (200) should be changed or replaced during transit, where conditioned replacements are available. Additionally, while the conditioning indicator (206) is shown as being included on the modular cover (202), it should be understood that the same or a similar device may also be included on the PCM cover (100) or on any other PCM fabric, structure, or feature described herein.

As another example of a PCM fabric implemented feature, FIG. 11 shows a perspective view of an exemplary envelope (300) that may be formed of PCM fabric as similarly described in the context of the PCM cover (100) and the modular cover (200). The PCM envelope (300) includes a body (302) and an openable flap (304) that define an interior envelope section (306) of varying dimension. The flap (304) may couple to the body (302) when closed using buttons, Velcro, adhesive, or other fastening means. The PCM envelope (300) may be conditioned as described with other PCM features, and goods may be placed in the envelope section (306). This may be useful for storing small and sensitive goods such as liquid medications or fragile electronics, as the envelope section (306) receives additional protection from temperature and shock. The PCM envelope (300) may itself be placed within another box or cargo, such as the cargo (44), as may be desired for particular goods.

II. PCM Panels

Several passive temperature management features that may be implemented with flexible PCM fabric have been discussed. Flexible covers like the PCM cover (100) and modular cover (200) are advantageous in that they can be flexibly fit and shaped onto goods as may be desired. However, rigid PCM features are also possible and provide a number of advantages when combined with or used as an alternative to flexible PCM fabrics and other temperature control features.

Rigid PCM components are generally referred to herein as “panels,” even where they include surface contouring or interior spaces designed to fit certain application. PCM panels may be applied to palletized cargo such as the cargo pallet (40), may be used as filler for palletized cargo or within boxes, and may be applied to the shipping container itself to provide additional physical protection and passive temperature control. PCM panels may also be used to fabricate containers such as boxes or envelopes (e.g., such as the PCM envelope (300)) where a rigid structure may be preferable to a flexible body.

As an example of a PCM panel, FIG. 12 shows a perspective view of a PCM panel (400). The PCM panel (400) is rectangular, though its shape and other dimensions (e.g., length, width, and depth) may be varied for a particular application as will be described below. A surface (402) of the PCM panel (400) fits the internal contents snugly and may provide a small amount of structural rigidity and conductive or reflective insulation, while the interior of the PCM panel (400) provides the majority of the structural rigidity. An edge (404) of the PCM panel (400) may be formed of the same material and material sheet as the surface (402) so that the interior contents of the PCM panel (400) may be sealed within a substantially uninterrupted exterior skin. As an example, this may include placing the formed interior structure of the PCM panel (400) within a vacuum bag or sleeve and then vacuum sealing the sleeve onto the interior structure to provide a rigid, durable, sealed panel.

FIG. 13 shows a cross sectional view of the PCM panel (400). An outer layer (406) makes up the surface (402) and the edge (404) of the PCM panel (400) and seals the interior layers. The material of the outer layer (406) may include one or more of a plastic or polymer, a paper product, a thermal foil, or other materials. The PCM panel (400) may support one or more interior layers, as may be desired for a particular application. As shown in FIG. 13, the PCM panel (400) includes a first layer (408), a core layer (410), and a second layer (412). The core layer (410) is the primary source of PCM capsules and rigidity, while the first layer (408) and the second layer (412) may provide additional PCM capsules, improved physical protection, improved insulation, or other characteristics.

The core layer (410) may be formed of a composite material that includes PCM capsules, structural fibers or other filler material, and a binding material such as an adhesive, rubber, or polymer that may be dried or cured to bind the structural material and PCM capsules into a rigid or semi-rigid piece. As an example, one implementation of the core layer (410) may include a mix of PCM capsules and polymer structural fibers suspended within an expanding urethane foam. As another example, a highly porous fibrous structure may be produced that may be permeated with a PCM capsule fluid that dries, cures, or is otherwise contained within porous gaps. As another example, a grid or netting of interconnected structural fibers may also be overlaid on each side of the core layer (410) and/or spread throughout the core layer (410) for additional durability.

The first layer (408) and the second layer (412) may be, for example, foam sheets to provide additional protection and insulation, rigid polymer gridworks to provide additional rigidity, or PCM fabrics such as those described above to provide additional physical protection and concentration of PCM capsules. The type and number of layers included in a particular panel may be varied greatly depending upon a particular application.

For example, some implementations of the PCM panel (400) include only the core layer (410) (e.g., a semi-rigid PCM capsule and fiber composite) and the outer layer (406) (e.g., a thermal foil wrapped vacuum sealed skin). Some implementations may additionally include PCM fabric layers as the first (408) and second layers (412), to provide additional shock and impact protection, insulation, and PCM temperature control. Some implementations may include multiple core layers, multiple outer layers, or multiple other layers, with any such variations being apparent to those of ordinary skill in the art in light of this disclosure.

As has been described, PCM panels (400) may be fabricated in various shapes and sizes by varying the number of layers, the thickness of layers, the shape of the core layer (410), or by separately fabricating and then coupling together multiple individual pieces (e.g., assembling 5 PCM panels to create a box). This flexibility allows PCM panels (400) to be created and used in a variety of applications for shipping containers. As an example, this could include applying panels to surfaces of goods, inserting panels between or within goods, using shaped panels to fill gaps within a container to provide additional temperature control and prevent shifting during transit, and other uses.

This could also include applying PCM panels (400) on one or more surfaces of a shipping container, as shown in FIG. 14, which shows a perspective view of the shipping container (30) with a plurality of PCM panels installed. The shipping container (30) is shown with the set of doors (34) opened. PCM panels may have a variety of surface textures, but are shown in FIG. 14 as having a dot-pattern texture to emphasize their location within the interior (36) of the shipping container (30). A set of wall panels (420, 422, 424) are installed on the walls of the interior (36), and may be held in place by, for example, friction, adhesives, clips or rails, or pocket portions of the structure (32) that are designed to receive a panel. A ceiling panel is installed on the ceiling of the interior (36) and may be held in place using similar means as the wall panels (420, 422, 424).

In some implementations the panels (420, 422, 424, 426) may be inserted into a set of rails that run along a surface of the interior and slid into place so that the rails align and hold them against the wall. In some implementations, a set of mechanical clips or grips (e.g., a spring grip, screw grip, or insertable grip) may be operated once the panel (420, 422, 424, 426) is in place to secure the panel. In some implementations, each panel may be secured in place by the combined set of installed panels (e.g., the rear wall panel (422) may be friction fit between the other wall panels (420, 424), and each of the set of wall panels (420, 422, 424) may be friction between the floor and a ceiling panel (426)). In some implementations, an air gap may be present between a wall of the interior (36) and an outer wall of the structure (32). In such cases, a panel may be inserted into the air gap between the inner and outer walls. As an example, a floor panel (428) is shown installed within a pocket below the floor of the interior (36).

A door panel (430) can also be seen installed on an interior face of one of the doors (34), while the other door (34) is shown without a panel. As can be seen, the exposed door (34) includes a set of contoured portions (38) along its inner face. The door facing portion of the door panel (430) is shown in FIG. 15, where a contoured inner surface (434) of the door panel (430) can be seen opposite a flat outer surface (432). The contoured inner surface (434) has been shaped to fit within the set of contoured portions (38) of the doors (34) and to expose the flat outer surface (432) when installed. The door panel (430) may be installed on each door using, for example, adhesives, guides or rails, mechanical clips, grips, or bolts, or other fastening means.

As can be seen in FIG. 14, a set of PCM panels may be fabricated in shapes and sizes to fit an interior of a shipping container. Once fabricated, the PCM panels may be conditioned to a desired temperature (e.g., at or below freezing) when not in use. When goods are shipped in the shipping container, the set of PCM panels may be removed from conditioning storage and installed within the shipping container. Once installed, goods may be placed in the shipping container. Further preparation may include inserting additional PCM panels within the interior of the shipping container (e.g., to fill gaps, separate goods, prevent shifting), installing PCM covers (e.g., such as the PCM cover (100)) on goods, and placing certain goods within PCM envelopes (e.g., such as the PCM envelope (300)), for example.

As another exemplary application of PCM panels, FIG. 16 shows a perspective view of a molded panel (440) that has been shaped to contain a medical device (50) during shipment. The medical device (50) may be, for example, an Mill machine, x-ray machine, or other scanning or imaging system. Temperature control, shock and impact control, and other protective measures are often advantageous or required when equipment such as the medical device (50) is shipped. The molded panel (440) may be constructed from one or more individual PCM panels (e.g., a combination of flat PCM panels such as the PCM panel (400) and contoured PCM panels such as the door panel (430)) to provide an outer shell (442) that houses an interior (444). During shipment of the medical device (50), two molded panels (440) (e.g., or more, such as where three or more separate panels may be fabricated to assembly and fully cover goods) may be assembled about the medical device (50) and coupled together with tape, wrap, rope or straps, or by being boxed within another structure or container. The molded panel (440) may be fabricated to custom shapes and sizes or fabricated to fit standard types and sizes of goods as may be desired. The molded panels (440) may be used similarly to other PCM features by conditioning each panel and then installed them on goods shortly before transit.

Production and use of various PCM features has been described in some detail.

Other variations and examples exist and will be apparent to those of ordinary skill in the art in light of this disclosure. For example, FIG. 17 shows a flowchart of a set of exemplary steps that may be performed to prepare and use panels with shipped goods. Initially, a set of characteristics may be determined (500) for a particular application for PCM panels or other features are desired. This may include determining the size and shape of goods, the size and shape of a shipping container interior, the type of goods being shipped and any associated temperature requirements, the presence and function of other active or passive temperature control features, and other details.

Based upon determined (500) details, one or more core layers may be shaped and produced (502). As an example, this may include fabricating core layers of a certain shape and size to fit an interior of a shipping container based upon determined (500) dimensions, or may include fabricating core layers of a certain thickness or providing multiple core layers based upon determined (500) temperature control requirements. Additional layers may also be created and/or applied (504) to the core layers, which may include adding additional structural substrates, PCM fabrics, reflective or non-conductive surfaces, and other layers. Selection of additional layers may also be base don the determined (500) characteristics, as shipping requirements, shipping container dimensions, and other factors may indicate a need for extra rigidity, physical durability, or PCM based temperature control.

After creating (502) the core layers and applying (504) additional layers, the assembly may be sealed within an outer layer material to produce (506) a usable panel. This may include sealing the layers within a thermal foil vacuum seal exterior skin, wrapping the layers in a plastic or polymer, or sealing the layers within a treated paper product. Produced (506) panels may then be conditioned (508) by placing them in a cool environment until a desired temperature is reached (e.g., a temperature of the core layer or innermost concentration of PMC capsules). Conditioning (508) may also include applying or placing conditioning indicators on panels as they are produced (506) or as they are conditioned (508). When panels have reached a desired temperature, they may be selected (e.g., based upon a total time of conditioning, a visual indication from a conditioning indicator, or other criteria) and installed (510) on or within a shipping container or a set of goods.

It should be understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. that are described herein. The following-described teachings, expressions, embodiments, examples, etc. should therefore not be viewed in isolation relative to each other. Various suitable ways in which the teachings herein may be combined will be readily apparent to those of ordinary skill in the art in view of the teachings herein. Such modifications and variations are intended to be included within the scope of the claims.

Having shown and described various embodiments of the present invention, further adaptations of the methods and systems described herein may be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the present invention. Several of such potential modifications have been mentioned, and others will be apparent to those skilled in the art. For instance, the examples, embodiments, geometrics, materials, dimensions, ratios, steps, and the like discussed above are illustrative and are not required. Accordingly, the scope of the present invention should be considered in terms of the following claims and is understood not to be limited to the details of structure and operation shown and described in the specification and drawings. 

What is claimed is:
 1. A passive temperature control device for one or more goods during shipment, the passive temperature control device comprising: at least one outer layer; at least one inner layer; and at least one core positioned between the at least one outer layer and the at least one inner layer, wherein the at least one core comprises a phase change material including a plurality of polymer microcapsules containing a liquid salt hydrate; wherein the passive temperature control device is configured to be conditioned in a cool environment to cool the phase change material to a desired temperature; wherein the passive temperature control device is configured to provide passive temperature control for the one or more goods during shipment.
 2. The passive temperature control device of claim 1, wherein the passive temperature control device comprises a cover configured to be positioned about at least a portion of the one or more goods.
 3. The passive temperature control device of claim 2, wherein the at least one outer layer and the at least one inner layer each include a flexible thermal foil that is configured to reflect radiant heat.
 4. The passive temperature control device of claim 2, wherein the at least one core includes a flexible cloth having a coating comprising a plurality of the polymer microcapsules containing the liquid salt hydrate.
 5. The passive temperature control device of claim 4, wherein the coating is configured to cure as a semi-flexible rubberized coating.
 6. The passive temperature control device of claim 2, wherein the cover includes a first flexible portion and a second flexible portion, wherein the first flexible portion is more flexible relative to the second flexible portion.
 7. The passive temperature control device of claim 2, wherein the cover includes a first edge and a second edge, wherein the first and second edges overlap.
 8. The passive temperature control device of claim 7, wherein the first and second edges are coupled with each other.
 9. The passive temperature control device of claim 1, further comprising a conditioning indicator coupled with the passive temperature control device, wherein the conditioning indicator is configured to indicate a temperature of the at least one core.
 10. The passive temperature control device of claim 1, wherein the passive temperature control device is formed as an envelope having a body and an openable flap that define an interior envelope section for receiving the one or more goods therein.
 11. The passive temperature control device of claim 1, wherein the passive temperature control device comprises a panel that is sufficiently rigid to provide physical protection to the one or more goods.
 12. The passive temperature control device of claim 11, wherein the passive temperature control device is enclosed in a continuous exterior skin.
 13. The passive temperature control device of claim 11, wherein the at least one core comprises a composite including the plurality of polymer microcapsules, a plurality of structural fibers, and a binding material.
 14. The passive temperature control device of claim 11, wherein the panel is insertable within a shipping container configured to receive the one or more goods therein.
 15. The passive temperature control device of claim 11, wherein the panel is molded to receive the one or more goods within the panel.
 16. A container for shipping one or more goods, wherein the container comprises: a structure defining an interior for storing one or more goods within the interior; and a passive temperature control device comprising: at least one outer layer; at least one inner layer; and at least one core positioned between the at least one outer layer and the at least one inner layer, wherein the at least one core comprises a phase change material including a plurality of polymer microcapsules containing a liquid salt hydrate, wherein the passive temperature control device is configured to be conditioned in a cool environment cool the phase change material to a desired temperature; wherein the passive temperature control device is configured to provide passive temperature control for the one or more goods stored within the container.
 17. The container of claim 16, wherein the passive temperature control device comprises a cover configured to be positioned about at least a portion of the one or more goods.
 18. The container of claim 16, wherein the passive temperature control device comprises a panel positioned within the interior of the container.
 19. A method of manufacturing a passive temperature control device for one or more goods during shipment comprising the steps of: fabricating a core comprising a phase change material including a plurality of polymer microcapsules containing a liquid salt hydrate; and applying additional layers to the core by sealing the core within an outer layer to produce a panel.
 20. The method of claim 19, further comprising: conditioning the panel by cooling the panel to a desired temperature; and installing the panel about the one or more goods to provide passive temperature control to the one or more goods. 